No. 39] ODONATA OF CONNECTICUT: COENAGRIONIDAE 73 



Abdomen: blue and black; terga largely blue, with black spot 

 on base of i, and apices of 2-6 inclusive, all of the dorsum of 7 

 black except a basal interrupted ring; dorsum of 10 black; terga 

 8 and 9 blue; anal appendages (Fig. 10, No. 17) short, black, the 

 superiors bifid, the two arms equal in length ; dorsal arm of supe- 

 rior appendages black at tip and forming a blunt hook when 

 viewed from above ; inferior appendages pale, dark at tips and 

 about as long as the superiors. 



Female. — Color black and yellow or blue. 



Head : with the blue of the male sometimes replaced with yellow. 



Thorax : similar to the male ; mesostigmal plates as in Fig. 1 1 , 

 No. 5. 



Abdomen: broad dorsal black stripes on segments 2-10, the 

 stripes contracted at the meson on the bases of terga 3-7 inclusive, 

 widened subapically on terga 2-7 ; first tergum with black basal 

 spot. 



Measurements: total length, male 27-31, female 27-31 mm.; 

 length of abdomen, male 21-25, female 22-24 n^"^- 5 length of hind 

 wings, male 15-17, female 16-18 mm.; width of hind wings, male 

 and female 3-4 mm. 



Connecticut. — West Thompson, 12 July, 1905 (H. L. V.) ; New Haven, 

 II June, IQ14 (B. H. W.) ; Guilford, 13, 27 July. 1920; Hamden, 4 July, 

 3 August, 1920. 30 May, 1922; Litchfield, 22 July, 1920; Branford, 21 

 July, 1920 (P. G.) ; New London, 8-22 June, 1921 (R. H. H.). 



New England. — May 26-August 30. 



Enallagma geminatum Kellicott 



Entomological News, 6: 239: 1895. 



Nymph. — Color usually green. 



Head : about three times as broad as long, elliptical ; the caudo- 

 lateral angles not projecting, and possessing few spines ; third 

 antennal segment longest, the second longer than the first, seg- 

 ments 1-3 or 1-4 dark in color; median lobe of the labium with 3 

 mental setae and sometimes a small fourth ; 5 lateral setae. 



Thorax: femora without dark rings near the apex, or with 

 very faint ones ; tarsal claws dark at the tips. 



Abdomen: with lateral keels on segments 1-8, the first without 

 spines or with 2 ; second with 3-5, third with an irregular single 

 row, 4-8 with irregular single rows with sometimes 2 spines at 

 their apices ; segment 9 has an irregular row of setae in line with 

 the keels of the preceding segments ; dorsum of segments 2, 3 

 and 4 hairy ; a darker line present just below the lateral keels on 

 segments 1-8; few or no spines on venter of 1-4. 



Gills: spatulate to lanceolate (PI. i. Fig. 7) without pigment 

 except in the smaller tracheae, and sometimes a trace along the 

 axes ; dorsal marginal spines of the median gill and ventral spines 

 of the lateral gills extending much less than half the length of the 



